Various embodiments of mass flow meters for flow media that work on the Coriolis Principle are known (see, for example, German Disclosure Documents 26 29 833, 28 22 087, 28 33 037, 29 38 498, 30 07 361, 33 29 544, 34 43 234, 35 03 841, 35 05 166, 35 26 297, 37 07 777, 39 16 285 and 40 16 907, European Patent Disclosure Documents 0 083 144, 0 109218, 0 119 638, 0 185 709, 0 196 150, 0 210 308, 0 212 782, 0 235 274, 0 239 679, 0 243 468, 0 244 692, 0 250 706, 0 271 605, 0 275 367 and 0 282 552, as well as U.S. Pat. Nos. 4,491,009, 4,628,744 and 4,666,421) and are increasingly being applied in practice.
Mass flow meters for flow media that work on the Coriolis Principle are basically divided into those whose pipes are designed to be straight, and those whose pipes are designed to be single or multi-curved, and a pipe loop. Another differentiation is made between those in question with only one pipe and those with two; in designs with two, they may be fluidally in series or in parallel. All these embodiments have advantages and disadvantages.
The mass flow meters in which the pipe/s is/are designed to be straight are simple in mechanical design and consequently can be produced at relatively low cost and the inner surfaces of the pipes are easy to process, for example, to polish. They also have low pressure losses. The disadvantage is that they have a relatively high natural frequency at a certain layout length. The embodiments of mass flow meters in which the pipe/s is/are designed to be curved have disadvantages where those with a straight pipe or pipes have advantages. But their advantage is that they have a relatively low natural frequency at certain layout lengths.